As a new generation of network transmission mode, the SDH is consisted of SDH Network Elements (NE) and used for synchronous information transmission, multiplex and cross connection on optical fibers. The SDH technique employs a uniform Network Node Interface (NNI) worldwide, which simplifies the processing of signal interconnection, transmission, multiplexing, cross connection and exchange. The SDH has a set of standardized information structure levels, referred to synchronous transfer mode STM-1, STM-4, STM-16 and STM-64, and also has a block frame structure that has rich overhead bits, i.e. the remain part in the bit stream of NNI except the net load, which can be used for network operation, administration and maintenance (OAM). The basic SDH network elements include synchronous optical cable system, Synchronous Multiplexer (SM), Add-Drop Multiplexer (ADM) and Synchronous Digital Cross Connection (SDXC) devices etc. Each of them has a uniform standardized optical interface, so they are compatible on an optical cable, i.e., devices of different vendors can be interconnected on an optical circuit. Nevertheless, administrative information for SDH devices of other vendors cannot be transparently transmitted over SDH devices of a vendor in prior arts.